%Nivelul Fermi in Siliciu-n

Ibinceanu Eduard-Constantin

Benga Alexandru-Cristian

%Nivelul Fermi in Siliciu-n.

%Date de intrare

kT_q=25.9e-3;

ni=1e10;

NA=logspace(13,18);

Ec=0.55.*(NA./NA);

Ev=-0.55.*(NA./NA);

Ei=0.*(NA./NA);

EF=Ei-kT_q*log(NA/ni);

semilogx(NA,Ec,'-',NA,Ev,'-',NA,Ei,'-',NA,EF,'-');

xlabel('Concentratia de dopare a siliciului-n N_A(cm^-^3)');

ylabel('Nivel Fermi E_F(eV)');

text(3*1e15,0.50,'E_c')

text(3*1e15,0.05,'E_i')

text(3*1e15,-0.37,'E_F')

text(3*1e15,-0.51,'E_v')

Problema 2

%Coeficientul de difuzie al electronilor.

%Date de intrare

N0=1e17;

D0n=35;

D1n=1.8;

d=0.6;

NA=logspace(14,20);

D0p=12.5;

D1p=1;

ND=logspace(14,20);

DnNA=D0n./(1+((NA./N0).^d))+D1n;

DpND=D0p./(1+((ND./N0).^d))+D1p;

loglog(ND,DpND,NA,DnNA)

xlabel('Concentratia de dopare N_A sau N_D (cm^-^3)');

ylabel('Coeficientii de difuzie D_n, D_p (cm^2/s');

text(1.5e15,4e1,'D_n')

text(1.5e15,1e1,'D_p')

Problema 3

%Rezistivitatea siliciului.

%Date de intrare

N0=1e17;

D0n=35;

D1n=1.8;

d=0.6;

NA=logspace(13,20);

ND=logspace(13,20);

D0p=12.5;

D1p=1;

kT_q=25.9e-3;

q=1.6e-19;

DnNA=D0n./(1+((NA./N0).^d))+D1n;

DpND=D0p./(1+((ND./N0).^d))+D1p;

un=DnNA/kT_q;

up=DpND/kT_q;

ron=1./(q.*un.*NA);

rop=1./(q.*up.*ND);

loglog(NA,ron,ND,rop)

axis([1e13, 1e20, 1e-4, 1e3]);

xlabel('Concentratia de dopare N_A sau N_D (cm^-^3)');

ylabel('Rezistivitatea (\Omega.cm)');

text(8e14,25,'Si-p')

text(4e14,4,'Si_n')